1  /* yesno.c -- read a yes/no response from stdin
       2  
       3     Copyright (C) 1990, 1998, 2001, 2003-2023 Free Software Foundation, Inc.
       4  
       5     This program is free software: you can redistribute it and/or modify
       6     it under the terms of the GNU General Public License as published by
       7     the Free Software Foundation, either version 3 of the License, or
       8     (at your option) any later version.
       9  
      10     This program is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      13     GNU General Public License for more details.
      14  
      15     You should have received a copy of the GNU General Public License
      16     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <config.h>
      19  
      20  #include "yesno.h"
      21  
      22  #include <stdlib.h>
      23  #include <stdio.h>
      24  
      25  /* Return true if we read an affirmative line from standard input.
      26  
      27     Since this function uses stdin, it is suggested that the caller not
      28     use STDIN_FILENO directly, and also that the line
      29     atexit(close_stdin) be added to main().  */
      30  
      31  bool
      32  yesno (void)
      33  {
      34    bool yes;
      35  
      36  #if ENABLE_NLS
      37    char *response = NULL;
      38    size_t response_size = 0;
      39    ssize_t response_len = getline (&response, &response_size, stdin);
      40  
      41    if (response_len <= 0)
      42      yes = false;
      43    else
      44      {
      45        /* Remove EOL if present as that's not part of the matched response,
      46           and not matched by $ for example.  */
      47        if (response[response_len - 1] == '\n')
      48          response[response_len - 1] = '\0';
      49        yes = (0 < rpmatch (response));
      50      }
      51  
      52    free (response);
      53  #else
      54    /* Test against "^[yY]", hardcoded to avoid requiring getline,
      55       regex, and rpmatch.  */
      56    int c = getchar ();
      57    yes = (c == 'y' || c == 'Y');
      58    while (c != '\n' && c != EOF)
      59      c = getchar ();
      60  #endif
      61  
      62    return yes;
      63  }